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chine with a UNITED' STATES PATENT OFFICE.

STEPHEN M. ALLEN,.0F DUXBURY, MASSACHUSETTS.

MANuFAb-runs or'A PAPER-PULP, are.

.,.SPEGIFICATIQN farming Part of Letters. Estant Non 253.95.13. .datedFebruary 14, 1882...

Application tiled August 30, 1881. (No specimens To all whom it mayconcern.- l

' Be it known that I, STEPHEN M. ALLEN, of

Duxbury, in the county of Plymouth and State of Massachusetts, haveinvented a new and useful Improvement in the Manufacture of Paper-Pulpand Leather-Board from Bark and other Wood Fiber, which improvement isfully set forth in the following specication.

This invention has for its object, namely the production of paper-boardor leather-boar although itis in part applicable to other purposes.

It relates to an improved process for making pulp from the brous partsof bark of trees, to the combination of bark pulp with other wood ber,and to an improved leatherboard from wood ber, and process of making thesame.

In order to prepare bark pulp in accordance ...with .this invention, the.,b1lrkissepatatedfr0m the tree-trunks in sheets, usually rst steamingor soaking the wood cut into strips of suitable length to make it comeoft more easily. The process described in Patent No. 229,307, granted toJas. Davy, Jr., June 29, 1880, be employed to advantage. By .means ofproper sharp cutters the bark can be removed alone, or with a layer ofthe new wood just be- This new wood I have found can be brilized morereadily than the part near the heart, and yields a very strong toughber. The sheets of bark, with or without the adhering layer of solidwood, are flattened between rollers and fed on a traveling apron orotherwise 'to a. revolving cutter or picker, which is properly gaged toremove the outer or refuse bark, which 'possesses no valuable ber, andleave the inner rind or bers cleaned and perfect. A machine like acommon planing-maplain revolvingknife or with a toothed cutter, andprovided with means such employed for regulating the @amount of materialtaken oft, will answer the purpose. The inner bark is then put through apicker which tears it into shreds, is treated with hot water or alkalinesolution, and beatenl into pulp. It may also be pulped in other ways,although the way described is deemed most advantageous. If it is to bemixed with other ber or with rag pulp, these can be groundsimultaneously with itin the machine forming the subject of myvapplication for patent tiled August 1,5, 1881, for improvement in themanumay facture of paper-pulp'from woodnnd other materials. Y

It may be here observed that the manufacture of paper-pulp from bark hasbeen heretofore suggested. It has, for example. been proposed to grindthe whole bark and to separate the fibrous from the non-brous portionsby washing or sifting. N one,howeve.r, of the processes proposedcontemplate the removal of the bark in' sheets, nor the separation ofthe .rough and useless bark in the manner indicated; nor do they coverthe specific process of-making pulp ns stated above. Inusin g this pulpit is always preferred to mix it with other iber,'although it canbe madeinto paper or board byitselt. It can be subjected to bleachingprocesses, if desired.

In order top .make leather or paper board inccordancm'xviththisinyentioninthe mostad vantageous .ground together inany suitable machine. The mixed pulp, which should contain aboutonethird bark and two-thirds solid-wood ber from new wood or old wood,or both, is placed in a beating-engine y wherein it can be heated. Whilehot it is thoroughly incorporated .with asphalt sizing. of pure asphaltmelted or softened with any mineral, vegetable, or animal oil, or withother resinous material, in connection with reduced alkalies mixed inhot water. The sizing is used in the proportion ol' about ve to tenparts to ninety or ninety-ve parts of pulp. When the materials are wellmixed the pulp is run oil onto a board-machine of any usual constructionand matie into sheets of leather or paper board of the desireddimensions. The sizing not only colors and sizes the leather or paperboard, but renders it nearly water-proof. Other coloring-matter orsizing can be introduced into the beating-engine, or they may beintroduced into the grinder, if desired. The board can also be embossedor painted, if desired. It is excellently adapted to the manufacture ofchair seats and backs, to trunk-coverings, as a substitute forpatent-leather in saddles and harness, tocap visors and trimmings, tocar-sheathing, machine-belting, rooting, washers for screw-nuts, &c.Paper-board may be made in the manner indicated with .various.proportions of solid-wood ber and bark ber,

of solid-wood ber alone, or of bark ber alone.

This sizing consists of a base -shreds in a picker,

More or less rag ber or ber from other paper-stock may alsobe mixed withthe wood ber.

Instead of grinding tbe solid wood and bark together, they may be madeinto pulp separately by grinding or other process, and then mixed in theboating-engine, or the bark, after being torn to pieces in the picker,can be added to the disintegrated or ground Wood ber in said engine.

In the sopa-ration of the rough useless bark from the fibrous portionsthe latter may be planed oiu the form of shavings, leaving the roughportions. j

Having now fully described my said invention and the manner of carryingthe sameinto eect, What I claim is y l'. The method of making pulp frombark by separating the rough from the fibrous portion, tearing thelatter into shreds by a. picker, soak ing, and heating, substantially asdescribed.

2. The method of makingbark pulp by removing the bark in sheets,separating the rough bark from the brous portions by planing, and thentearing the fibrous portions to soaking them, and beating them intopulp, substantiallyv as described.

3. The method of preparing bark pulpl or making paper, paperboard, andlike articles, by mixing the bark pulp with or without pulp from solidwood or other material, while hot, with asphalt sizing or other sizing,substantially as described.

4. Paper-pulp, paper, paper or leather board, or other manufacture ofpaper containing bark pulp alone or with other ber sized with asphaltsizing, substantially as described.

5. The combination in paper-pulp, paper, paper or leather board, and thelike, of bark pulp and solid wood pulp, substantially as d-` scribed.

6. A paper or leather board of bark pulp and solid-wood or other pulp,sized and colored with asphalt/ sizing, or other sizing and coloringmaterials, substantially as described.

In testimony whereof I have signed this specification in the presence oftwo subscribing witnesses.

' STEPHEN M. ALLEN.

Witnesses:

H. G. ALLEN, C. J. HEDRIGK.

